摘要
为改善频率曲线高尾部对实测洪水大值段的拟合效果,提高大重现期洪水设计值精度,研究LQmoments(LQM)法在洪水频率分布参数估计中的应用。LQM法是L-moments(LM)法的扩展方法,具有较好的不偏性和稳健性。以6个年最大洪峰流量系列为例,进行P-Ⅲ分布和GEV分布LQM法的参数估计,以累积相对偏差平方和(δ)、RMSE和平均绝对误差(MAE)为标准,评价和比较LQM法和LM法对P-Ⅲ和GEV分布参数的估计精度和拟合效果。结果表明,P-Ⅲ分布LQM法取得了很好的拟合效果,6个洪峰流量系列中,5个系列的最优参数估计方法为LQM法,其中3个系列的最优分布为P-Ⅲ分布;与LM法相比,LQM法能更好地拟合洪水序列大值部分,提高大重现期设计值估计精度,是洪水频率分布参数估计的有效方法。
To improve the fitting effect of frequency curve and the calculation accuracy of design flood of large return period,application of LQ-moments(LQM)method in parameter estimation of flood frequency distribution is studied.Parameters of P-Ⅲ distribution were estimated for six annual maximum flood series,and the estimation accuracy and fitting effect were evaluated and compared with LM methods and GEV distribution using δ、RMSE and MAE.The results show that LQM method results in satisfying fitting effect and P-Ⅲ distribution is the best-fit distribution for three flood series and the LQM method is the optimal estimation method for five flood series.Compared with LM method,LQM method improves the estimation accuracy of design value of large return period,and is an effective method for the parameter estimation of flood frequency distribution.
作者
魏婷
WEI Ting(Taiyuan University of Technology,College of Water Resources and Engineering,Taiyuan 030024,China)
出处
《水文》
CSCD
北大核心
2023年第4期27-32,44,共7页
Journal of China Hydrology
基金
山西省自然科学基金项目(20210302124697)。
关键词
LQM法
LM法
P-Ⅲ分布
洪水频率分析
参数估计
LQ-Moments
L-Moments
P-Ⅲ distribution
flood frequency analysis
parameter estimation
